Centrifugal-pump



B. J. KIME.

CENTRIFUGAL PUMP. APPLICATION FILED NOV.21,19|9.

1,353,915. Patentedsapt. 28,1920.

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B. J. KIME.

CENTRIFUGAL PUMP.

APPLlcATloN FILED N0v.21.1919.

Patented Sept. 28, 1920.

2 SHEETS-SHEET 2.

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UNITED STATES I Alxrlazlar oFFicE.

BENJAMIN J'. KIME, 0F SENECA FALLS, NEW YORK, ASSIGNOR 0F ONE-FCURTH T0RANSOM R. MICKS, 0F SENECA. FALLS, NEW YORK. I

cEN'iRIrUGAL-PUMP.

To` aZZwhom t may concern: v l Be it known that/I, BENJAMIN J. KIME,

of SenecaFalls, in the county of ySeneca,`

in the State of New York, have invented new and useful Improvements inCentrifugal Pumps, of which the following, taken in connection with theaccompanying drawings, is a full, clear, and exact description. Thisinvention relates to certain improvements in centrifugal pumps andrefers more particularly to means for automatically regulating thevolume of liquid delivered by the'pump according to the head or degreeof back pressure produced by the liquid.

The ordinary centrifugal pump is de- 'signed to discharge a certain'volume of liquid against a given pressure or head under-a predeterminedspeed of the impeller which requires 'a given motor powerto maintain thedesired capacity \of delivery,

, but it is found that if .the head of the same pump is materiallyreduced it greatly increases the volume of discharge which, in turn,overloads the impeller and lrequires more power for its operationthanwunder the normal head for which the pump and its motive power weredesigned, so that if the head is materially/reduced the pump anditsmotive power will cease t0 properly function. 1

The main object of my invention is to provide simple and efficient meansto automatically maintain approximately the same volume of delivery fora given period of time under varying heads or height of water column sothat a pump designed for a certain head Imay be eiiiciently' operatedIunder reduced heads.

' In pumps of this character the intake opening in the impeller case isusually coaxial with the rotary impeller while' the outlet is tangentialthereto so. that therotation of the vimpeller serves to `draw the liquidthrough the intake into the central opening in the impeller and toexpelit through .passages lleading/'fromthe center to the periphery ofthe impeller 'into the outlet, and l `j-6- of the case.

lone of the specific objects of this invention is to provide anautomatic piston valve be? degree lof lopen communication b etween theintake and impeller passages will be normally reduced to a comparativelysmall de' I Qgree, but is causedto gradually increase as Specificationof Letters Patent.

rotatable in the ease-1 and Patented Sept. 28, 1920.

Application led November 21,' 1919. Serial No. 339,531.

means'of a coaxially slidable piston valve y having a piston headcommunicatingfwith the outlet through the impeller chamber and itsinnerend extended into the impeller across the adjacent' ends of the passagestherein and provided with radial openings registering more or less withsaid passages under varying pressures as the valve is operated by liquidpressure in one direction against the action of a suitable retractingspring hereinafter described.

Other objects and uses relating to specific parts of the pump will bebrought out in the following description.

In the drawings Figure 1 is a longitudinal vertical sectional view of acentrifugal pump embodying the vfeatures of my invention.

Fig. 2 is an enlarged transverse vertical sectional View of the samepump taken on line 2-2, Fig. 1.

Fig. 3 'is an enlarged longitudinal sectional view of the detachedimpeller and piston valve.

As illustrated, the centrifugal pump coml prises a base -1- havinglengthwise jour-v and also having a circumferentially extending ozutlet-`6- terminating tangentially at An impeller -8'- is secured to a"rotary shaft -9- which is journaled inthe bearings -2- and-3 3 saidimpeller being A rovided witha central opening l0-,- an aseriesofpassages ,-11'-, said opening -10- vbeing coaxial with `the inlet -5-of the case while .the passages --Vlllead from the central opening inthe impeller to the outlet A tubular valve T12` is mounted coaxiallyl ofandwithin the opening -10- in the impeller /to slidef endwise or axiallyacross the inner ends of the passages l1- and i-s provided with anannular shoulder L--13-- coperating with a portion +14- of.l theimpeller for limiting .the closing` iol movement of the valve toapartially open position 'and thereby maintaining a restrictedcommunication between the interlor of the valve and outlet passages -11-until the fluid pressure is sufficient to overcome the tension of itsretracting spring.

To this end the tubular valve l2- is provided with av series of radialpassages *15- normally 4 extending in opposite directions from andbeyond the stop shoulders --13` and 14- so that the eifective size ofthe opening between the interior of the valve and passages 1lmay beenlarged by theinward lmovement of the valve from its normal position.

This opening movement of the. valve is produced automatically by thepressure of the fluid expelled by the impeller into ,the outlet -6-,said pressure being variable inversely as the head or height of thecolumn, of liquid from the terminal end 7- of the outlet.

For this purpose is provided a tubular preferably formed integral withthe tubular valve l2- coaxial with the inlet -5- of the case so that thevalve and piston together constitute a tubular sleeve which is slidableendwise or axially within the opening l0- and an additional guideopening 1T- in the case, the interior of said sleeve communicating withthe inlet -5- of the case.

The piston 16- is `formed by an enlarged central portion of the sleeveof which its supporting shaft designed, it

it forms a part and is located in the impeller chamber -18` between theouter end of the impeller and the adjacent side of the case where it isexposed to the pressure of the liquid from the outlet 6` through theimpeller' chamber.

' A retracting spring 19- is located within the sleeve, as -20-, formingthe valve 12- and the piston -16- and has voneend bearing against theinner wall of the impeller and its other end engaged with van inturnedannular shoulder 21- on the outer end of the sleeve for retractingsaidsleeve and thereby normally holding its shoulder *13*- in engagementwith the companion shoulder -14- or, in other words, normallymaintaining the valve in a partly open position.

It is now evident that as the impeller and -9- are rotated by anysuitable means unnecessary to herein illustrate, the liquid will bedrawn into the central inlet 5* and thence through the sleeve 20- fromwhich it will pass through the openings -l5- and passages -llof theimpeller and thence through the outlet passage (not sho-wn) rising fromthe terminal end -7- of the outlet -6-. N ow, if the pump is operatingunder normal hea-d and power for which it was will continue to deliverthe re- .tensioned relatively quired volume of liquid, but should thehead be reduced for any reason tending to increase the volume ofdelivery, the decreased pressure of such liquid upon the piston -16-will allow the latter to be moved axially toward its normal position bythe spring 1Q-'for maintaining approximately the same volume of deliveryas that for which the pump was designed under the maximum head.

It is to be understood that pumps of this character are designed tooperate under an approximately predetermined head and volume ofdelivery, and that in many instances the pump is installed to operateunder a considerably lower head than that for which it was designed,resulting in a corresponding reduction of back pressure and aproportionately increased volume of delivery unless some means isprovided'for preventing such increased volume of delivery.

The valve *l2- and its retracting spring -19- are normally adjusted toallow the passage of water therethrough at the beginning of theoperation of the pump and until the head reaches a predetermined(relatively low) level, whereupon as the head and consequent backpressure increases, the valve will be further gradually opened againstthe action of its retracting spring 19- and may continue to further'openuntil the maximum head and volume of delivery for which the pump isdesignedis reached, at'which time, the capacity of delivery will, ofcourse, be practically constant.

In the event, for any reason, the pump should be used with aheadconsiderably less than that for which it was designed, the back pressurewill, of course, be correspondingly reduced and will allow acorresponding -return of the 4valve 12- toward its normal' position bythe spring -19, the tension of the spring tending to move the valvetoward its normal position being so to the maximum head l pressuretending to open the valve against the action of the spring, that whenthe pump is used with a head materially below that for which it wasintended, the gradual movement of the valve toward its normal 1 positionby the spring under the reduced pressure will automatically maintainapproximately the same volume of delivery as when operated under themaximum head with the valve full open.

On the other hand, if the passage for the water to the impeller were toremain at its full capacity and the head were materially reduced, thevolumeof delivery would be corres ondingly increased beyond the vollhaving an `inlet and passages communicat- 12 ing respectively with thefirst-named 'inlet and outlet, a valve controlling communication betweenthe inlet and passages of the impeller and normally having restrictedcommunication with said passages, a piston actuated in one direction bypressure of the 'fluid discharged by the impeller and connected to thevalve for gradually` opening the latter as the liquid pressure increasesbeyond a certain degree, and retracting means for the valve and piston.

2. In ,a centrifugal pump the combination y of an impeller case havingan inlet and an outlet, a rotary impeller in said case having an inletand passages communicating respectively With the inlet and outlet of thecase, f

a valve movable across the inner ends of said passages, means'actuatedby pressure of the liquid discharged by the impeller for graduallyopening the valve as the pressure increases, and retracting means forsaid valve and piston.

3. In a centrifugal pump the combination of an impeller case having aninlet and an outlet, an impeller rotatable in said case and providedWit-l1 an inlet and passages registering respectively with the inlet andoutlet of the case, said inlets being coaxial with the axis of movementof the impeller, a tubular valve coaxial with said inlets and movableaxially across said passages, a piston actuated in one direction bypressure of the expelled fluid, and transmitting its motion to saidvalve for opening the latter as the pressure increases, and retractingmeans for the valve and piston.

4. In a centrifugal pump the combination 'of' an impeller case having aninlet and an outlet, an impeller rotatable in said case and providedwith a. central opening coaxial with the inlet of the case and alsohaving passages communicating with the outlet of said case, a valvemovable in the central opening of the impeller across said passages andprovided With an inlet communicating with that of the case, coperativemeans between the impeller and valve Jfor limiting the closing movementof said valve to a partly open position, a spring normally holding thevalve in its partially closed position, and means actuated by pressureof the expelled iuid for gradually opening said valve against the actionof said spring When the pressure is suiicient to overcome the tension ofthe spring.

In witness whereof l have hereunto set my hand this 10thvday ofNovember, 1919.

BENJAMIN J. KME.

Witnesses:

H. E. CHASE, MARGARET L. S'roUP.

